Interest-calculator



2 Sheets-Sheet 1.

M. TODD.

INTEREST CALCULATOR.

. Patented Feb. 6 Wl W IIT/IEENTOR 77 www@ ATTORNEYS.

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M. TODD.

INTEREST CALCULATOR.

No. 271,949. Patented Feb.6,1883.

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" i i N E WTTNESSER: R5 'A INVENTOR;

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UNITED vSTATES PATENT OFFICE.

MARSHALL TODD, OF DANVILLE, INDIANA.

lNTEREST-CALCULATO R.

SPECIFICATION forming part of Letters Patent No. 271,949, dated February 6, 1883.

Application filed April 17,1882.

To all whom itmay concern:

, Be it known that I, MARSHALL TODD, of Danville, in the county of Hendricks and State of Indiana-,have invented a new and Improved Interest-Calculator, of which the following is a full, clear, and exact description.

The object of my invention is to provide a new and improved device for facilitating the computing of the interest on any desired sum of money for any desired number of days, months, or years.

The invention consists in a box having its top divided into a series of I"subdivisions, marked one day, two days, three days#7 &c.,which subdivisions are each provided with an aperture, through which the interest-numbers on sliding cards in the box can be seen. rlhese cards are each provided with a row of numerals from 0 to 9, inclusive, which numerals 'on one card express units, on the other tens, or hundreds, or thousands. By drawing out the cards until the numerals expressing the desired number of units, tens, hundreds, &c., will show in apertures in the cover of the box, the interest on these sums will appear in the apertures of the subdivision in the cover of the box.

Reference is to be had to the accompanying drawings, forming part of this specification, in which similarletters of reference indicate corresponding parts in all the iigures.

Figure 1 is a plan view of the box containing the sliding cards of my improved interestcomputer. Fig. 2 is a cross-section of the same. Fig. 3 is a plan view ofthe chart containing the interest on thousands. Fig. 4 is a plan view of the card containing the interest on hundreds. Fig. 5 is a plan view of the card containing the interest on tens. Fig. 6 6 is a plan View of the card containing the interest on units.

The interest-computer is contained ina box provided with a cover, J, which is provided with a number of subdivisions, a a, which are marked one day, two days, three days,77 &c., one month, two months, three months, &c., or one year, two years,77 three years, Src. The subdivisions a are arranged in vertical rows, and at one end each subdivision a is provided with an aperture or opening, H, through which numerals on charts or cards below the cover can be seen. As the (Model.)

subdivisions a are arranged in vertical rows, the apertures H at the ends of these compartments will also be in vertical rows, as shown. Above the uppermost aperture, H, of each row apertures G G G2 Gr3 are provided in the cover J of the box. This box contains four or more charts or cards, A, B, O, and D, subdivided in the same manner as the cover J of the box.

The cardAis provided on theleft-hand side and along the upper edge with a row of numerals from 0 to 9, inclusive, which numerals express thousands. For instance, 2 stands for two thousand, and 8 for eight thousand, and so on. Below these numerals, or in corresponding positions in the subdivision c, the interests for one, two, three, or more days are arranged. For instance, in the subdivision a corresponding in position with the subdivision marked one day7 on the cover J the interests on one thousand, two thousand, three thousand, four thousand, &c., dollars for one day are arranged below the numerals l 2 3 4, &c., or they are arranged correspondingly. In the subdivision c corresponding with the subdivision marked two days on the cover J the interests on one thousand, two thousand, three thousand, 85e., dollars for two days are arranged, and so on for any number from one to nine of thousands of dollars, and for from one to thirty days and one to twelve months, and as many years as may be desired.

The card B (shown in Fig. 4) is provided along the upper edge, in the space adjacent to that similarly numbered in the card A, with a row of numerals from 0 to 9, inclusive, which numerals indicate hundreds. The card B is divided into subdivisions a2 a2, Src., in the same manner as the cover J, and these subdivisions contain numerals representing the interests on one hundred, two hundred, three hundred, and four hundred dollars, arranged in the same order as the numerals l 2 3 4, Sie., for one, two, three, four, tive, 85o., days, or months, or years. This cardB is above the card A, and for this reason must be provided with longitudinal slots L L, through which the interest-numbers on the lower card, A, can be seen.

The card or chart C is provided with the numerals from 0 to 9, inclusive, arranged along its upper edge, in the space adjacent to that IOO 

